untreated

adjective

un·​treat·​ed ˌən-ˈtrē-təd How to pronounce untreated (audio)
: not treated
untreated wastewater
especially : not improved or controlled medically
an untreated case of pneumonia
untreated diabetic patients

Examples of untreated in a Sentence

untreated wool
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
And there is evidence to back this — a Yale University review of insurance claims showed while 60% of women with significant symptoms of menopause seek treatment, almost 75% are left untreated. Emma Burleigh, Fortune, 18 Oct. 2025 These modified beads were far better at avoiding immune responses compared to untreated nanoplastics. Neetika Walter, Interesting Engineering, 17 Oct. 2025 For decades, leaders looked the other way as the Tijuana River Valley filled with trash, sediment and untreated wastewater. Paloma Aguirre, San Diego Union-Tribune, 16 Oct. 2025 Left untreated, the condition is usually fatal in the first one to two years of life. New Atlas, 16 Oct. 2025 See All Example Sentences for untreated

Word History

First Known Use

15th century, in the meaning defined above

Time Traveler
The first known use of untreated was in the 15th century

Browse Nearby Words

Cite this Entry

“Untreated.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/untreated. Accessed 28 Oct. 2025.

Medical Definition

untreated

adjective
un·​treat·​ed -ˈtrēt-əd How to pronounce untreated (audio)
: not subjected to treatment
an untreated disease

More from Merriam-Webster on untreated

Last Updated: - Updated example sentences
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